O2 Sensor Low Voltage, Both banks.

[JonRussell18]

My little brother has a 98 LS1 Camaro and we recently put a fresh built transmission in with a super tight 2500 stall and I was doing some trans tuning on it and noticed something. The O2 Sensors at WOT just flat line at 100mv or so. I have no clue as to why. It's throwing a code for both O2s. Both are which are brand new. It does have some KR oddly enough. The car runs good otherwise, has gone 111 mph in the 1/4 mile.

Car has the stock tune engine wise as I don't have a wideband, so I'm not gonna mess with it until I do. Which is why I find this odd. Besides the fan temp and disabling EGR/AIR stuff, the tune engine wise hasn't been touched.

Car has:
Longtube Headers, Cat-less Y-pipe, SLP LM2 Cat-Back
LS6 Intake, Ported Throttle Body and a Lid.

I've read that this could mean it's absurdly lean, like 15:1 lean, but I find that hard to believe since it's been racing like this for years now. Well before I got HP Tuners to even know it was happening. Maybe he's lucky? No clue. I'm new to tuning so I'm not sure if I should change anything, I've always read to only tune with a wideband, but I have read the O2s should be around 890mv at WOT, and on my personal car (98 T/A), they're around 870mv at WOT.

Here's a log of the car.
98 Camaro Trans Tune.hpt

[blindsquirrel]

All you can say about it if your only tool is a narrowband is that less than 450mV is leaner than stoich and more than 450mV is richer than stoich. A tiny change in voltage can be a huge change in mixture.

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If narrowbands are not more than 450mV in power enrichment then you have a serious problem.

[JonRussell18]

Do you suggest adding fuel? Like I said, I don't have a wideband so it would be a blind guess at best, but running at 11.1 would be a lot safer than 15:1. Gonna try cleaning the MAF tomorrow on the off chance it's dirty, I also have my old MAF from my car that I could throw on and see if it acts any different.

[blindsquirrel]

I suggest tuning instead of tooning. Get a wideband. No other way to confirm what it's doing in PE/open loop.

[gtstorey]

Fuel pressure issues?

[SiriusC1024]

Get a wideband...

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